The typical accuracy specification of a meter is of ±0.5% (Class 5) or of ±0.2% (Class 2) thus, for example, of ±1.25 V and ±0.5 V respectively for a 250 V voltage reading. Such a voltage variation observed for a short connection having a resistance of 10 mΩ respectively corresponds to a variation of current of 125 A and 50 A in this connection. An absolute voltage reading of a meter, used alone, allows a priori only detecting electrical non-compliances exhibiting high levels of voltage deviations. According to a meter-to-meter differential view, the comparison of the voltage of a meter with the other meters sharing the same low-voltage network may indicate lower level anomalies. For this purpose, it would be useful to be able to correct the voltage measurement calibration divergences between meters connected to a common network to allow a more accurate detection of anomalies. According to a time-differential view for a same meter, the voltage variations related to the variations of load currents contain relevant information for detecting non-compliances. US 2015/0241488 (Sonderegger) proposes a method using a linear regression for linking the voltage variations to the variations of current measured by a meter and inferring an impedance correlation thereof. An abnormally high impedance may indicate a bypass. Also, it is mentioned that a low convergence of the regression is an indicator of a bypass used only a part of the day. The method has the disadvantage of considering only the voltage variation of a meter as a function of its consumption regardless of the other voltages and consumptions of the other meters, so that it mixes two resistance values, namely the network resistance and the meter-to-network connection resistance. It has been discovered in the context of the present invention that these two resistance values, and also their dispersion, are altered differently depending on the type of ENCs present. It would be desirable to have a more accurate method than those known in the prior art, the method also being able to provide a means for detecting load manipulations that may lower the apparent connection resistance of a meter so as to deceive certain prior art methods as that proposed in US 2015/0241488 (Sonderegger). US20130191051 (Stocker et al.), US20160117326 (Steigler) and U.S. Pat. No. 9,013,173 (Veillette) provide examples of other prior art methods.